ஐ.எஸ்.எஸ்.என்: 0974-276X
Frank M You, Pingchuan Li, Santosh Kumar, Raja Ragupathy, Zhengnan Li, Yong-Bi Fu and Sylvie Cloutier
Flax (Linum usitatissimum L.) is an important crop with many characteristic features such as its abundant essential ω-3 fatty acids for human nutrition. Fatty acid (FA) biosynthesis in plants, including flax, involves several consecutive steps governed by different gene families. Using in silico gene mining and comparative analysis, genome-wide gene identification and characterization were performed for six gene families related to FA biosynthesis, including KAS, SAD, FAD, KCS and FAT. We identified 91 FA-related genes from flax cv. CDC Bethune genome, from which seven previously cloned genes were validated. The newly identified 84 FA-related genes include 14 novel genes from the KAS family, two from the SAD family, 13 from the FAD2 family, three from the FAD3 family, 38 from the KCS family and 14 from the FAT family. Out of the 91 genes identified, 88 were duplicated as a consequence of recent whole genome duplication events, in which 13 FAD2 genes were hypothesized to have evolved from tandem gene duplication events followed by a whole genome duplication event and, more recently, by a single gene deletion. The six gene families described here are highly conserved in plants and have diverged anciently. These newly identified flax genes will be a useful resource for further research on FA gene cloning and expression, QTL identification, marker development and marker-assisted selection.